JPH0110609Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a vehicle acceleration detection device.

In the case of two-wheeled vehicles, a phenomenon occurs in which the front wheels rise and the rear wheels sink during a sudden start or sudden acceleration, and conversely, the front wheels sink and the rear wheels rise during sudden braking. As a result, the passenger's riding posture changes significantly,
This seriously impairs steering stability.

In contrast, as the present applicant has already proposed in Utility Application No. 1988-29088, the compression resistance of the rear wheel hydraulic shock absorber is increased during sudden starts and accelerations, and conversely, during sudden braking, the front wheel Measures have been adopted to stabilize the riding posture by increasing the compression resistance of the side hydraulic shock absorbers.

However, the vehicle height adjustment means that adopts such a measure indirectly detects changes in the acceleration of the vehicle by detecting the vehicle height, and has a problem in that its configuration is extremely complicated and expensive. .

On the other hand, a weight attached to the tip of a strain rod is placed in silicone oil, and a strain gauge is used to detect the amount of swing of the weight when the vehicle accelerates. An acceleration detector is provided that detects a voltage value obtained through the resistance winding by sliding the energizing brush over the resistance winding, and uses this as acceleration data.

However, in the former detector using a strain gauge,
Although the detection accuracy is high, the noise is large and the output is small, so a noise filter or amplifier is required.
It has become relatively expensive. In addition, in the latter case using a resistance winding, in a vehicle with a lot of vibration, the slide contact part may vibrate and the energizing brush may separate from the resistance winding.
This caused problems such as damage to the resistor winding.

The present invention solves these conventional problems by fixing one end of a flexible member within a container, and providing the flexible member with adjustable natural frequency and damping. A vehicle acceleration detection device that can detect vehicle acceleration with high precision by providing a balance mass and a shutter at the other end and interposing the shutter between a light emitting element and a light receiving element installed at the bottom of the container. This is what we propose.

The details of the present invention will be described below with reference to specific examples.

FIG. 1 and FIG. 2 are one example of this, and 1
consists of two case members 1a and 1b, with screws 2
A leaf spring 4, which is a flexible member, is housed in the case 1 and has one end fixed to the insertion portion of the screw 2 between the case members 1a and 1b. At the lower end of this leaf spring 4, there are shutters 5 and 6 that also serve as balance masses (weights) to sandwich it.
are fixed by screws 7, and these shutters 5 and 6 are interposed between the light emitting element and the light receiving element of the photointerrupter 8 so as to be able to pass freely therethrough. In addition,
This photo interrupter 8 is provided with a slit so that changes in the amount of light shielded by the shutters 5 and 6 can be detected with high precision. Reference numerals 9 and 10 denote rubber sheets serving as rubber dampers attached to both sides of the leaf spring 4 above the shutters 5 and 6.

In the acceleration detector having such a configuration, when the vehicle to which the case 1 is attached is suddenly accelerated or braked, the leaf spring 4 swings leftward or rightward centering on the upper part in FIG. 1. Although the amount of rocking changes depending on the magnitude of the acceleration of the vehicle, vibrations and deformation of the leaf spring 4 due to this fluctuation are suppressed by the rubber sheets 9 and 10. This prevents the leaf spring 4 from swinging out.
The damper for the leaf spring 4 can be adjusted by selecting the thickness of the rubber sheets 9 and 10. In addition, by selecting the number of stacked leaf springs 4, leaf springs 4
It is also possible to adjust the natural frequency of

On the other hand, due to the swinging of the leaf spring 4, the shutters 5, 6 also swing, and the shutters 5, 6 also swing.
6, light enters the light receiving element from the light emitting element of the photo interrupter 8, and a signal corresponding to the amount of shielding by the shutters 5 and 6 of the slit of the photo interrupter 8, that is, an acceleration signal, is generated. This output is used to control the hydraulic shock absorbers for the wheels.

FIG. 3 shows another embodiment of the invention. This has bellows 11 and 12 interposed between the inner wall of each case member 1a and 1b and each rubber sheet 9 and 10, and has a certain resistance to air flow between these bellows 11 and 12. Through hole 13
is the leaf spring 4 and the rubber sheet 9,
10 is bored. Note that the shutters 5 and 6 are fixed with rivets 14. By doing so, the natural frequency and damping of the leaf spring 4 can be adjusted using the air flow resistance. Further, although not shown, similar adjustments can be made by selecting the number of stacked leaf springs 4 or by selecting the thickness of the rubber sheets 9 and 10.

FIG. 4 shows yet another embodiment of the present invention. In this case, the case portions 1a and 1b are diagonally widened at the bottom and contracted at the top. The upper case members 1a and 1b
A support rubber 15 of an appropriate length is interposed in the gap between the inner wall of the leaf spring 4 and the mounting base of the leaf spring 4. Therefore, by appropriately selecting the length of the support rubber 15, the swinging fulcrum of the leaf spring 4 can be adjusted up and down as desired. In this way, the natural frequency of the leaf spring 4 can be adjusted by changing the support span.

FIG. 5 shows yet another embodiment of the present invention. The difference between this and previous examples is that
Instead of the leaf spring 4, a thin wire spring 16 such as piano wire is used. Incidentally, shutters 5 and 6 are also attached to the lower end of the thin wire spring 16, with the photo interrupter 8 interposed therebetween. Even in such an embodiment, acceleration detection similar to that described above can be performed in a photoelectric configuration.

Note that the rubber sheets 9 and 10 are attached to the spring 16.
It goes without saying that damping adjustment and natural frequency adjustment can be performed by attaching a rubber damper having the same function as, for example, a rubber tube, or by applying the support rubber 15.

By the way, by arbitrarily selecting the number of photo interrupters 8 and the shapes of shutters 5 and 6,
The gain of the photo interrupter 8 can be adjusted.

In FIG. 6a, two sets of photo interrupters 8 are prepared, and the amount of light from these two sets of slits 8a and 8b is transferred to a shutter 1 having notches 17 and 18 on both sides of the lower end.
9 shows what is controlled. According to this, by moving the shutter 19 in front of the slits 8a and 8b, as shown in FIG. The output is a straight line Q,
An output characteristic that changes like R can be obtained.

In FIG. 7a, one set of photo interrupters 8 is prepared, and a knife-edge type shutter 20 having a notch 21 is moved in front of the slit 8c. It will look like Figure b. According to this, the output has a characteristic as shown by a straight line S along the slope of the knife edge. Therefore, the zero point of this acceleration and deceleration is selected at the center O of the inclined straight line S, and above the O point, acceleration is set, and below the O point, deceleration is set.

FIG. 8a shows a first inclined portion 23 on the shutter 22.
A, a cutout section 23 consisting of a horizontal section 23b and a second inclined section 23c is provided, and this section is moved in front of a set of photo interrupters 8. The horizontal portion 23b is provided to prevent the amount of light shielding from changing due to minute movements of the shutter 22 near the zero point of acceleration.

According to this, the output characteristics of the photo interrupter 8 are as shown in FIG. 8b, and the dead zone is defined by a straight line T
, it is possible to make this a continuous characteristic with inclined straight lines U and V showing acceleration and deceleration on both sides. That is, by detecting the output level, the acceleration/deceleration of the vehicle can be measured with high accuracy.

In the embodiments shown in FIGS. 6 and 8, the shutters 19 and 22 are shaped so that the amount of light shielding does not change near the zero point of the acceleration/deceleration, that is, the output characteristics of the photo interrupter 8 are Because it is configured in a shape that produces dead zones P and T near the zero point,
The compression resistance of the hydraulic shock absorber does not change even with small changes in acceleration/deceleration near the zero point, which has a great practical effect.

In this way, the gain of the photo interrupter can be adjusted as desired by appropriately designing the shapes of the shutters 19, 20, and 22.

In summary, in the present invention, one end of the flexible member inside the case is fixed, this flexible member is provided so that the natural frequency can be adjusted and the damping can be adjusted, and the balance mass and the other end of the flexible member are provided. By providing a shutter and movably interposing the shutter between the light emitting elements of the photo interrupter installed in the case, the flexible member swings when the vehicle accelerates or decelerates, allowing the shutter to adapt to the shape of the shutter. The advantage is that acceleration and deceleration can be measured electrically and with high accuracy. Furthermore, since the natural frequency and damping of the flexible member can be adjusted, it is extremely useful in practice.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing one embodiment of the acceleration detection device according to the present invention, FIG. 2 is a front sectional view of the same, and FIGS. 3, 4, and 5 are side sectional views of other embodiments. , FIG. 6a, FIG. 7a, and FIG. 8a are explanatory diagrams showing the gain adjustment method of the photo interrupter, and FIG. 6b, FIG. 7b, and FIG. 8b are output characteristic diagrams of the photointerrupter, respectively. It is. 1... Case, 4, 16... Flexible member, 5,
6, 19, 20, 22...Shutter, 8...Photo interrupter.

Claims (1)

[Claims for Utility Model Registration] (1) One end of a flexible member is fixed within a case, and this flexible member is provided so that its natural frequency and damping can be adjusted, and a balance mass is provided at the other end of the flexible member. and a shutter, the shutter being movably interposed between the light emitting element and the light receiving element of the photointerrupter installed in the case,
A vehicle acceleration detection device configured to detect the amount of deflection of the flexible member corresponding to the acceleration of the vehicle as a change in the amount of light shielded between the two elements by the shutter. (2) The vehicle acceleration detection device according to claim 1, wherein the flexible member is a leaf spring. (3) The vehicle acceleration detection device according to claim 1, wherein the flexible member is a thin wire spring. (4) The vehicle acceleration detection device according to claim 1, wherein the shutter is configured in a shape that does not cause a change in the amount of light shielding near the zero point of acceleration.